JPH072829B2 - Laminate - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a laminated board, and more particularly to a multilayer printed circuit board which is excellent in flame retardancy, heat resistance and electrical characteristics and has a small shrinkage factor upon curing.

[Conventional technology]

Conventionally, as a laminated material for a multilayer printed circuit board, a brominated modified resin or a phenol resin using an addition type flame retardant, an epoxy resin, a polyimide resin or the like has been mainly used for imparting flame retardancy. In particular, a large computer is required to have a high density, and a polyimide resin having excellent heat resistance and dimensional stability is used. However, in recent years, with the increase in the speed of arithmetic processing of large-scale computers, a printed circuit board having a low dielectric constant is required to improve the signal transmission speed. As such a low dielectric constant laminated material, a laminated plate made of tetrafluoroethylene (PTFE) resin or polybutadiene resin has been developed. Examples of this type of laminated plate include, for example, Proceeding N.G.P.C.O.N., (1981
Year) 160 to 169 (Proc. NEPCON (1981) P.P160
-169) and JP-A-55-126451.

Further, as a flame-retardant resin composition having a low dielectric constant, a composition comprising a poly (p-hydroxystyrene) derivative and epoxidized polybutadiene is disclosed in JP-A-61-33050.

[Problems to be solved by the invention]

However, the PTFE laminated plate has the problems that the resin is thermoplastic and the glass transition temperature is low, so the coefficient of thermal expansion is large at high temperatures and the dimensional stability is not sufficient. Etc. are worried. Also, PT
Since there is no suitable solvent for FE, the bonding method by heating, melting and pressure bonding is generally used, but it has a drawback that the melting temperature is very high. In addition, the polybutadiene resin has a drawback that it is flammable in terms of its molecular structure, and in order to impart flame retardancy, an additive type flame retardant such as decabromodiphenyl ether, triphenyl phosphate, tribromophenyl methacrylate, It is necessary to add a reactive flame retardant such as tribromophenyl acrylate, and the addition of these causes a problem that the original polybutadiene resin and electrical characteristics, heat resistance and dimensional stability are impaired.

An object of the present invention is to provide a flame-retardant low-dielectric-constant laminated material capable of high-density wiring comparable to that of a polyimide laminated material, as a material replacing conventional polyimide-based multilayer printed wiring boards used in large-scale computers. It relates to a molten laminate.

[Means for solving problems]

The gist of the present invention resides in that (a) the general formula (Wherein A is a halogen group, R ₁ is an alkenyl group having 2 to 4 carbon atoms, an alkenoyl group, and m is 1 to 4), and is a prepolymer of a poly (p-hydroxystyrene) derivative. And (b) an epoxy-modified polybutadiene, and (c) an aromatic maleimide compound in a thermosetting resin composition.

The thermosetting resin composition of the present invention includes, as the compound represented by the general formula (I), vinyl ether, isobutenyl ether, allyl ether of poly (p-hydroxystyrene), acrylic acid ester and methacrylic acid ester. , Bromides such as epoxy methacrylate.
These may be used alone or in combination of two or more as desired.

In the epoxy-modified polybutadiene, specific examples of the glycidyl ether-based epoxy resin used for modification include diglycidyl ether bisphenonol A, diglycidyl ether 2,2′-dibromobisphenol A, diglycidyl ether 2,2. ′, 4,4′-Tetrabromobisphenol A, diglycidyl ether 2,2′-dimethylbisphenol A, diglycidyl ether 2,2 ′, 4-trimethylbisphenol A, phenol novolak type epoxy resin, orthocresol It is a novolak type epoxy resin. These may be used alone or in combination of two or more, if desired.

Further, specific examples of the aromatic maleimide compound include N,
N'-m-phenylene bismaleimide, N-N'-p-phenylene bismaleimide, N, N'-4,4'-diphenylmethane bismaleimide, N, N'-4,4'-diphenyl Ether bismaleimide, N, N'-methylenebis (3-chloro-
p-phenylene) bismaleimide, N, N'-4,4'-diphenyl sulfone bismaleimide N, N'-m-xylene bismaleimide, N, N'-4,4'-diphenylcyclohexane bismaleimide, N, N'-4,4'-diphenylpropane-bis-maleimide, 2,2'-bis [4-4-maleimidophenyloxy) phenyl] propane, 2,2-bis [3-methyl-4- ( 4-maleimidophenoxy) phenyl] propane, 2,2-bis [4- (4-maleimidophenoxy)
Phenyl hexafluoropropane, 2,2-bis (4-maleimidophenyl) hexafluoropropane, 1,3-bis (3-
Maleimidophenoxy) benzene, 3,3'-bismaleimide benzenephenone and other bismaleimides and N-phenylmaleimide, N-3-chlorophenylmaleimide, N-
o-Tolylmaleimide, Nm-tolylmaleimide, Np
-Tolylmaleimide, N-o-methoxyphenylmaleimide, Nm-methoxyphenylmaleimide, N-p-methoxyphenylmaleimide, N-benzylmaleimide, N-pyridylmaleimide, N-hydroxyphenylmaleimide, N-
Acetoxyphenylmaleimide, N-dichlorophenylmaleimide, N-benzophenonemaleimide, N-diphenylethermaleimide, N-acetylphenylmaleimide,
Etc. are monomaleimides. These may be used alone or in combination of two or more, if desired.

In the present invention, the aromatic maleimide compound is superior in heat resistance to the aliphatic type.

Further, by adding a radical polymerization initiator and an epoxy curing agent to the thermosetting resin composition containing the above general formulas (I), (II) and (III), the curing reaction can be accelerated.

Typical examples of the radical polymerization agent include benzoyl peroxide, dicumyl peroxide, methyl ethyl ketone peroxide, t-butyl peroxylaurate, di-t-butyl peroxyphthalate, dibenzyl oxide, 2,5-dimethyl. -2,5-di (t-butylperoxy)
Hexane, t-butyl cumyl peroxide, t-butyl hydroperoxide, di-t-butyl peroxide, 2,5-
Dimethyl-2,5-di (t-butylperoxy) hexyne (3), diisopropylbenzene hydroperoxide, p-menthane hydroperoxide, pinane hydroxide, 2,5-dimethylhexane-2,2-dihydroperoxide , Cumene hydroperoxide, etc. These are preferably 0.1 to 10 relative to 100 parts by weight of the resin composition.
Add parts by weight.

Typical examples of epoxy curing agents are 4,4'-diaminodicyclohexylmethane, 1,4-diaminocyclohexane, 2,6-diaminopyridine, m-diphenylenediamine, p.
-Phenylenediamine, 4,4'-diaminodiphenylmethane, 2,2'-bis (4-aminophenyl) propane, benzine, 4,4'-diaminophenyloxide, 4,4'-diaminophenylsulfone, Bis (4-aminophenyl) methylphosphine oxide, bis (4-aminophenyl) phenylphosphine oxide, bis (4-aminophenyl) methylamine, 1,5-diaminonaphthalene, m-xylylenediamine, 1,1′- Bis (p-aminophenyl) furatane, p-xylylenediamine, hexamethylenediamine, 6,6'-diamino-2,2'-dipyridyl, 4,4'-diaminobenzophenone, 4,4'-diaminoazobenzene, Bis (4-aminophenyl) phenylmethane, 1,1'-bis (4-aminophenyl) cyclohexane, 1,1'-bis (4-amino-3-methylphenyl) cyclo Hexane,
2,5-bis (m-aminophenyl) -1,3,4-oxadiazole, 2,5-bis (p-aminophenyl) -1,3,4-oxadiazole, 2,5-bis (m- Aminophenyl) thiazolo (4,5-d) thiazole, 5,5'-di (m-aminophenyl)-(2-2 ') bis (1,3,4-oxadiazolyl), 4,4'-diaminodiphenyl ether , 4,4'-bis (b-aminophenyl) -2,2'dithiazole, m-bis (4-p-aminophenyl-2-thiazolyl) benzene, 4,4'-diaminobenzanilide, 4,4'-diamino Phenyl benzoate, N, N'-bis (4-aminobenzyl) -p-phenylenediamine, 4,4'-methylenebis (2-dichloroaline), benzoquanamine, methylguanamine, tetramethylbutanediamine, phthalic anhydride, Trimellitic anhydride, Pyromellitic anhydride, Anhydrous Nzophenone tetracarboxylic acid, ethylene glycol bis (anhydrotrimellitate), glycerol tris (anhydrotrimellitate), maleic anhydride, 2-methylimidazole, 2-phenylimidazole, 2-ethyl-4-methyl There are imidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole and the like, and at least one or more kinds thereof are used. It is appropriate to use the compounding amount in the range of 0.1 to 30 parts by weight, preferably 0.3 to 10 parts by weight, based on 100 parts by weight of the epoxy-modified polybutadiene.

Further, the radical polymerization initiator and the epoxy curing agent can be used together if necessary.

The blending ratio of the thermosetting resin composition can be variously changed as necessary. Generally, when the blending ratio of the poly (p-hydroxystyrene) derivative of the general formula (I) is increased, the flame retardancy and the mechanical strength are improved, but the flexibility is lowered,
The shrinkage factor during curing tends to increase. General formula (II)
When the blending ratio of the epoxy-modified polybutadiene of is increased, the flexibility and the adhesiveness to the copper foil are improved, but the heat resistance tends to be lowered, and when the blending ratio of the general formula (III) aromatic maleimide is increased. In addition, flame retardancy and heat resistance are improved, shrinkage upon curing is reduced, and dimensional stability tends to be improved.

The preferred range of the composition is 10 to 60% by weight of the formula (I), particularly 20 to 40% by weight (II) 10 to 50% by weight, especially 10 to 30% by weight (III) 20 to 70% by weight, Particularly, 30 to 60% by weight, these three kinds are prepared within the above range.

The composition of the present invention may contain an aromatic amine as a fourth component, if necessary.

Examples of aromatic amines include 4,4′-diaminodiphenylmethane 4,4′-diaminodiphenylsulfone 4,4′diaminodiphenyl ether 2,2-bis [4- (4-aminophenoxy) phenyl]
Propane 2,2-bis [4- (4-aminophenoxy) phenyl]
Hexafluoropropane 4,4'-bis (3-aminophenoxy) biphenyl 1,3-bis (3-aminophenoxy) benzene and the like.

Next, a general method for manufacturing a laminated plate in the present invention will be described.

First, a poly (P-hydroxystyrene) derivative, an epoxy-modified polybutadiene, and an aromatic maleimide are dissolved in an organic solvent to prepare a varnish. As the organic solvent, for example, toluene, xylene, acetone, methyl ethyl ketone, methyl isobutyl ketone, N, N-dimethylformamide, N-methylylpyrrolidone, dimethyl sulfoxide, trichloroethylene, trichloroethane, methylene chloride, dioxane, ethyl acetate and the like can be used.

If necessary, the varnish may be heated and preliminarily reacted to adjust the fluidity of the resin, the gelation time, and the like when the laminated plate is manufactured. Also, a coupling agent may be added to improve the adhesion to the substrate. A radical polymerization initiator and an epoxy curing agent are added to the prepared varnish to prepare a varnish for impregnation. Next, the obtained varnish for impregnation is impregnated and coated on a sheet-shaped substrate and dried at room temperature to 170 ° C. to obtain a prepreg having no tackiness. The setting of the drying temperature at this time depends on the solvent and the initiator used. Finally, a required number of the obtained prepregs are stacked and a heat curing reaction is performed at 100 to 250 ° C. under a pressure of 1 to 100 kgf / cm ² to obtain a laminated plate.

As the sheet-shaped substrate, almost all those generally used for laminated materials can be used. As the inorganic fiber, various glass fibers such as E glass, C glass, A glass, S glass, D glass, YM-31-A glass and Q glass using quartz containing SiO ₂ , Al ₂ O ₃ etc. And there are ceramic fibers. Examples of the organic fibers include aramid fibers containing a polymer compound having an aromatic polyamideimide skeleton as a component.

[Action]

The reason why the shrinkage rate of the resin composition of the present invention upon curing is small is unknown. It is considered that this is caused by the blending of the maleimide compound.

Since the curing shrinkage rate is small, the accumulation of stress on the cured product such as the laminated plate at the time of curing is small, and accordingly, the occurrence of cracks is small.

〔Example〕

Example 1 50 parts by weight of methacrylic acid ester of brominated poly (p-hydroxystyrene) (molecular weight 7,000 to 12000, bromine content 42%), 30 parts by weight of polybutadiene modified with diglycidyl ether bisphenol a, 2,2 ' 20 parts by weight of -bis [4-4 (-maleimidophenoxy) phenyl] propa was dissolved in a mixed solvent of 100 parts by weight of methyl isobutyl ketone and 150 parts by weight of acetone, and the mixture was heated and stirred at 50 to 70 ° C. Furthermore, 0.5 parts by weight of 2,5-dimethyl-2,5 di (t-butylperoxy) hexane (3) as a radical polymerization initiator and 2 parts by weight of benzoguanamine as a curing agent for epoxy were added and completely dissolved by stirring. Get a varnish.

Next, the varnish was degassed under reduced pressure while heating at 40 to 50 ° C. with an evaporator to remove the solvent to obtain a solid resin composition.
Further, the resin composition is put in a mold that has been subjected to a mold release treatment, and 130 to 150
It is heated to ℃ to make it liquid and degassed under reduced pressure to remove bubbles.
Min, 200 ° C for 120 minutes, 230 ° C for 120 minutes to obtain a resin plate.

Examples 2 to 13 and Comparative Examples 1 to 6 Resin plates were obtained in substantially the same manner as in Example 1 with the compounding compositions shown in Tables 1 and 2.

In Example 10 and Comparative Example 4, the acrylic acid ester of poly (p-hydroxystyrene) bromide has a molecular weight of 7,000-1200.
0, bromine content 45%, in Example 11 and Comparative Example 5, allyl bromide poly (p-hydroxystyrene) has a molecular weight of 7,000
˜12000, bromine content 43%, and epoxy methacrylic acid ester of poly (p-hydroxystyrene) bromide used in Example 12 and Comparative Example 6 had molecular weight of 7,000 to 12000 and bromine content of 35%. .

The main characteristics of the resin plates according to the above-mentioned Examples and Comparative Examples are described below.
Shown in the table.

Example 14 Methacrylic acid ester of brominated poly (p-hydroxystyrene) (molecular weight 7,000 to 12000, bromine content 42%) 50 parts by weight, polybutadiene modified with diglycidyl ether bisphenol A 30 parts by weight, 2,2 ' 20 parts by weight of bis [4- (4-maleimidophenoxy) phenyl] propane, 100 parts by weight of methyl isobutyl ketone and 1 part of dimethylformamide
It was dissolved in 50 parts by weight of the mixed solvent and heated and stirred at 100 to 120 ° C. for 30 minutes. Furthermore, 0.5 parts by weight of 2,5-dimethyl-2,5 di (t-butylperoxy) hexane (3) as a radical polymerization initiator and 2 parts by weight of benzoguanamine as a curing agent for epoxy were added and completely dissolved by stirring. I got a varnish.

A glass cloth (E glass, thickness: 0.1 mm) was impregnated with this varnish, and air-dried at room temperature and dried at 150 ° C. for 10 to 20 minutes to obtain a tack-free prepreg. Next, 10 of the prepregs were stacked and heated at a pressure of 40 kg · f / cm ² and a temperature of 130 ° C. for 30 minutes, and further pressed at 170 ° C. for 1 hour and 220 ° C. for 2 hours to obtain a laminated plate.

Examples 15 to 21 and Comparative Examples 7 to 12 Laminates were obtained in the same manner as in Example 14 with the compounding compositions shown in Table 4.

In Example 19, poly (p-hydroxystyrene) bromide
Acrylic acid ester has a molecular weight of 7,000 to 12,000 and a bromine content
45%, in Example 20, allyl bromide poly (p-hydroxystyrene) has a molecular weight of 7,000 to 12000, bromine content of 43%,
In Example 21, poly (p-hydroxystyrene) bromide
Epoxy methacrylate ester has a molecular weight of 7,000 to 12,000,
A bromine content of 35% was used.

Comparative example 1 of epoxy resin laminate and polyimide resin laminate
Set to 1,12.

Comparative Example 13 50 parts by weight of 1,2-polybutadiene prepolymer and 50 parts by weight of cresol novolak type epoxy modified polybutadiene are dissolved in xylene to obtain a varnish having a solid content of 20 to 30% by weight. Furthermore, 2 parts by weight of dicumyl peroxide as a radical polymerization initiator and 2-ethyl-4 as an epoxy curing agent.
A laminate was obtained in the same manner as in Example 13 except that 1 part by weight of methylimidazole was added.

Table 5 shows the main characteristics of the laminates according to the examples and the comparative examples.

Example 22 The resin composition shown in Table 6 was used, the prepreg obtained by the method shown in Example 13 was used, and copper foil (35 μm thick) having the surface roughened on the prepreg side was laminated on both sides, and the pressure was applied. 30kgf / cm
^2. Heat at 130 ℃ for 30 minutes, and then at 170 ℃ for 1 hour 2
It was pressed at 00 ° C. for 2 hours to obtain a copper-clad laminate. The thickness of this insulating layer is about 100 μm. The obtained copper-clad laminate is formed with an inner layer circuit pattern such as a signal layer, a power supply layer and a matching layer by a photo etching method, and the copper surface of the circuit pattern is processed by the following method to form a double-sided wiring unit circuit. A sheet was formed.

Solution composition: (1) Concentrated hydrochloric acid 300 g, cupric chloride 50 g, distilled water 650 g (copper surface roughening).

(2) Sodium hydroxide 5g, trisodium phosphate 10g, sodium chlorite 30g, distilled water 955g (stabilization of copper surface).

After the above processing is completed, the prepreg resin sheet having the structure shown in FIG. 1 is used to form the circuit conductor layer 2.
30 layers are formed, 170 ℃, pressure 40kg / cm ² , 170 ℃ for 90 minutes, 220 ℃
Adhesion was performed under conditions of 90 minutes to prepare a multilayer printed circuit board.

The multi-layered adhesion was performed by inserting guide pins into the holes provided on all four sides of the sheet to prevent misalignment. After the multi-layered bonding, a hole having a hole diameter of 0.3 mm or 0.6 mm was drilled with a microdrill and plated with chemical copper to form a through-hole conductor 4. Next, the outermost layer circuit was formed by etching to form a multilayer printed board.

In this embodiment, the thickness is about 3.5 mm × 570 mm × 420 mm, the line width is 70 μm and 100 μm, two types (channel / grid) are 2-3 lines / 1.3 mm, and the gap between layers is about 100 μm.
I got the following: The glass cloth was about 30% by volume of the insulating layer.

1, 3 are insulating layers, 2 are circuit conductor layers, 4 are through holes, 1 is the above-mentioned copper clad laminate, and 3 is a prepreg resin sheet.

Examples 23 to 29 and Comparative Examples 14 to 17 Multilayer printed circuit boards were manufactured in the same manner as in Example 22 with the resin compositions shown in Table 6.

Table 7 shows the results obtained by cutting out a part of the multilayer printed circuit board and measuring the solder heat resistance and the thermal shock resistance.

In addition, the thermal decomposition temperature was 5% measured for 10 mg of a crushed resin cured product in an air atmosphere at a temperature rising rate of 5 ° C./min.
The temperature when the amount was reduced was defined as the thermal decomposition temperature.

The coefficient of linear expansion was obtained by measuring the coefficient of thermal expansion in the thickness direction at a temperature rising rate of 2 ° C./min and the amount of change from 50 ° C. to 200 ° C.

The volumetric shrinkage rate during curing was determined from the difference between the specific gravity of the solid before curing and the specific gravity after curing. The bending strength is 180 mm at room temperature under the condition that the laminated plate is cut into 25 × 50 mm, the distance between fulcrums is 30 mm and the bending strength is 1 mm / min.
It was measured at ° C.

The relative permittivity was measured according to JIS C6481 and the capacitance at a frequency of 1 MHz was measured to obtain the relative permittivity.

In addition, solder heat resistance, bending characteristics, and JIS C6481 were also used. Solder heat resistance was checked at 260 ° C for 300 seconds for abnormal appearance.

Flame retardancy was measured according to the UL-94 vertical method. Thermal shock test: -60 ℃ to + 125 ℃ 1 cycle As a result, the cycle in which the crack enters is measured.

The resin composition of the present invention has a smaller volumetric shrinkage upon curing than a conventional resin composition having a low dielectric constant, and has good moldability.

Further, the laminated material using the resin composition of the present invention has a low dielectric constant characteristic like the polybutadiene resin generally known as a low dielectric constant material, and is currently applied to a multilayer printed board of a large computer. Compared with the existing epoxy-based materials and polyimide-based materials, the relative permittivity can be changed from 4.7 to 3.5, so the signal transmission delay time can be reduced by 15%.

Furthermore, by producing a multilayer printed circuit board using the resin composition of the present invention, a substrate having excellent thermal shock characteristics can be obtained.

〔The invention's effect〕

According to the present invention, a resin molded product having a small shrinkage ratio can be obtained, and a heat-resistant and flame-retardant low-dielectric-constant laminate having good crack resistance can be provided.

[Brief description of drawings]

FIG. 1 is a cross-sectional perspective view of a multilayer printed board which is an embodiment of the present invention. 1 ... Board, 2 ... Circuit, 3 ... Prepreg sheet, 4
…… Through hole.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Akira Nagai Akira Nagai 4026 Kuji Town, Hitachi City, Ibaraki Prefecture Hitate Works, Ltd., Hitachi Research Laboratory (72) Inventor Masahiro Ono 4026 Kuji Town Hitachi City, Ibaraki Prefecture Nitate Works Co., Ltd. Hitachi Research Laboratory (72) Inventor Toshikazu Narahara 4026 Kuji Town, Hitachi City, Ibaraki Prefecture Hitachi Research Laboratory, Hitachi, Ltd. (56) References JP-A-55-127425 (JP, A) JP-A-55-126452 (JP) , A) JP-A-55-73726 (JP, A) JP-A-55-73728 (JP, A) JP-A-61-243844 (JP, A) JP-A-62-192406 (JP, A)

Claims (1)

[Claims] 1. A fibrous base material comprising the general formula (a) (Wherein A is a halogen group, R ₁ is an alkenyl group having 2 to 4 carbon atoms, an alkenoyl group, and m is 1 to 4), and is a prepolymer of a poly (p-hydroxystyrene) derivative. And (b) general formula (In the formula, B is a glycidyl ether-based epoxy copolymer, and n is a number of 1 to 100), and a thermosetting resin composition containing (c) an aromatic maleimide compound is contained. A laminated board in which prepregs formed by laminating are formed.